Unexpected results from pressure switch and tank adjustment

Users who are viewing this thread

Zayd

Member
Messages
46
Reaction score
5
Points
8
Location
Michigan
First thing is first -- this is my first post since learning that Terry passed and I want to acknowledge the great community he built here. I am certainly grateful for it, as are many like me.

As I work through projects in my 1991 house, I've finally decided to learn enough (mostly from this forum) about the low water pressure problem we've had since we moved in 2.5 years ago. We came from city water pressure, so the drop was very noticeable. Based on what I learned here, this was my course of action:

1. I checked the pressure switch setting and, based on the pressure gauge, found that cut-out was set to 40psi (I forgot to check cut-in pressure).
2. I cut power to the well pump and raised the cut-in to 38 psi, which put the cut-out at 64 psi (not sure why the differential is not a standard 20 psi).
3. I opened a faucet and drained the pressure tank to nothing, then adjusted the pressure tank to 35 psi.
4. I restored power, let the pump pressurize the system, and went up to check pressure at the fixture that is the source of most of my wife's complaints: the shower. Here's the mystery: not only did the pressure not increase, but it seems that it actually dropped slightly. After about 10 minutes with the shower running, the pressure was lower than I had ever perceived it from the shower.
6. Afterwards, I went directly downstairs to check the system pressure -- 54 psi.

I am befuddled. I changed nothing but what I indicated above. Shouldn't this have resulted in ~50% more pressure than before? I've attached a picture of my setup. Yes, my brine tank is my wifi center until the basement project is complete!
 

Attachments

  • IMG_0263.JPG
    IMG_0263.JPG
    90.3 KB · Views: 98

Fitter30

Well-Known Member
Messages
4,475
Reaction score
831
Points
113
Location
Peace valley missouri
First replace gauge they do go bad. Did u adjust center nut the smaller screw adjust cut out. Shower head could be blocked with minerals. Soak whole head in vinegar over night and look at the holes and use a old toothbrush to clean it. Sinks pull aerator to inspect. Added gauge after the water filter to check pressure drop through it. Filter, softener and valves ( unless full port) all have pressure drop. Another gauge with hose bib fitting can measure pressure after most of the pressure drops if the softener is feeding one.
 
Last edited:

Valveman

Cary Austin
Staff member
Messages
14,732
Reaction score
1,330
Points
113
Location
Lubbock, Texas
Website
cyclestopvalves.com
With 54 PSI you should have plenty of pressure in the shower. I would open that bypass valve for the filter and softener. I think they are clogged and restricting the flow. You also have more than 20 PSI between on and off because you messed with the little adjustment screw in the pressure switch. You should never mess with the little screw. Do all pressure switch adjustments with the larger adjustment screw. Loosening off all the way on the smaller adjustment will get you back to 20 PSI differential or very close.

You could also just have low shower pressure because the pump is cycling on and off between 38 and 64 PSI. Without a Cycle Stop Valve the pump will cycle on and off from 38 to 64 over and over while taking a shower. That means for a few seconds you will have strong 64 PSI, but in a few more seconds your pressure will be almost half that much before the pump comes back on at 38 PSI. The low end of the pressure switch is not much different than when you had the switch set at 20/40.

With no restriction from the filter or softener, adding a Cycle Stop Valve will make the pressure so strong you will no longer even need soap in the shower. Lol! With the size tank and pressure switch setting you have now, the CSV1A could be set to deliver a strong constant 60 PSI. That means your pressure will stay at 60 PSI constant even if you are in the shower for a month.

It is your water system. You can have so much pressure you could wash a car with your shower pressure. You just have to make it happen. Asking questions is the first step. Constant pressure from a Cycle Stop Valve is the solution.

 

Zayd

Member
Messages
46
Reaction score
5
Points
8
Location
Michigan
First replace gauge they do go bad. Did u adjust center nut the smaller screw adjust cut out. Shower head could be blocked with minerals. Soak whole head in vinegar over night and look at the holes and use a old toothbrush to clean it. Sinks pull aerator to inspect. Added gauge after the water filter to check pressure drop through it. Filter, softener and valves ( unless full port) all have pressure drop. Another gauge with hose bib fitting can measure pressure after most of the pressure drops if the softener is feeding one.
Thanks -- shower head is new and clean. Good call on the pressure gauge -- I will pick up a new one today.

With 54 PSI you should have plenty of pressure in the shower. I would open that bypass valve for the filter and softener. I think they are clogged and restricting the flow. You also have more than 20 PSI between on and off because you messed with the little adjustment screw in the pressure switch. You should never mess with the little screw. Do all pressure switch adjustments with the larger adjustment screw. Loosening off all the way on the smaller adjustment will get you back to 20 PSI differential or very close.

Thanks, Cary. I bypassed the filter and softener and the pressure was unaffected. I let the shower run a couple of minutes, although I expect that I'd see an immediate increase in pressure if the filter/softener was the problem and I bypassed them. On the pressure switch, I did not touch the small adjustment screw, only the large. It's possible that the previous owner did, so I will do as you suggest and back it off to get back down to 20.

Even with pump cycling, I should be noticing a substantial pressure increase in the shower now. But your point is taken -- the CSV does make sense as a permanent solution. I've read your literature on it and watched the videos on your site. It sounds like the right way to go, but I do want to solve this particular puzzle as it seems to indicate that I have a separate problem somewhere.
 
Last edited:

Valveman

Cary Austin
Staff member
Messages
14,732
Reaction score
1,330
Points
113
Location
Lubbock, Texas
Website
cyclestopvalves.com
If a pressure gauge goes to zero when the tank is emptied and the pump is off the gauge is usually still good. But a gauge can be cheap to replace. I like the cheap gauges better than the liquid filled expensive ones, because you can see any flickers in the pressure. Bypassing the filters should have made an immediate difference if that was the problem. If the pump is still cycling on and off while a shower is running, there must be some other restriction. You can get a test gauge that screws to an outside hose bib. That way you can get a pressure reading further down the line. You can even get a reading at the connection to the washing machine that way. If the pressure at the tank is higher than the test gauge on the washer, there is a restriction between the gauges somewhere. You need to figure out the problem so you can get good pressure, then the CSV will make the pressure even better.
 

LLigetfa

DIYer, not in the trades
Messages
7,516
Reaction score
588
Points
113
Location
NW Ontario, Canada
If mineral deposits form under the diaphragm of the pressure switch, it can lower the cut-in which effectively increases the spread.

Poor pressure at the shower could be due to friction loss on long runs of undersized piping or could be due to government mandated flow restrictors in the showerhead or valve body. I don't let the government dictate my shower pressure so the first thing I do is to locate and remove the restrictor if possible.

If the shower is on an upper floor then gravity will cause a loss of 0.43 PSI per foot of elevation.
 

Zayd

Member
Messages
46
Reaction score
5
Points
8
Location
Michigan
You can get a test gauge that screws to an outside hose bib. That way you can get a pressure reading further down the line. You can even get a reading at the connection to the washing machine that way. If the pressure at the tank is higher than the test gauge on the washer, there is a restriction between the gauges somewhere. You need to figure out the problem so you can get good pressure, then the CSV will make the pressure even better.

Good idea. I'll pick up a gauge tonight to test pressure at the hose bibs further downstream and hopefully isolate the area where the restriction lives.


If mineral deposits form under the diaphragm of the pressure switch, it can lower the cut-in which effectively increases the spread.

Poor pressure at the shower could be due to friction loss on long runs of undersized piping or could be due to government mandated flow restrictors in the showerhead or valve body. I don't let the government dictate my shower pressure so the first thing I do is to locate and remove the restrictor if possible.

If the shower is on an upper floor then gravity will cause a loss of 0.43 PSI per foot of elevation.

Ranch home, and the showers in question are fed by 3/4" copper runs until they reduce to 1/2" within a few feet of the mixing valves. I did check the shower heads for restrictors but did not find any. I removed the shower hose to test water at the outlet and the flow is still low, regardless of the hot/cold mix.

How's the flow in shower with straight cold?. Is there a bathtub?

I checked the other bathroom's tub spout and pressure is low there as well, even with straight cold.
 

Zayd

Member
Messages
46
Reaction score
5
Points
8
Location
Michigan
Well, this is embarrassing. The mystery is solved.

I purchased a thread-on pressure gauge and checked pressure at the three hose bibs. Two were at system pressure, the farthest was only 2psi under. Since those lines come off the main before the filter/softener, that pointed back to Cary's original suspicion that the problem was there. Indeed, the problem was in the sediment filter. I must have let it go longer than usual based on the last filter change date I wrote on my housing sticker. The cartridge was gummed up with sediment (looked like iron) like I haven't seen it before. I don't know if something disturbed the well or what, but that definitely was the culprit.

A new filter cartridge later and I have good pressure again all over the house. Thanks for the guidance, everyone.

Cary, the CSV is still on my list, especially with plans to run a 1" irrigation supply line outside for the future. I'll search the forum and see what's out there before I start a new thread.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks